SWC 250 S2 Skimmer mods

[lastlight]

I would imagine anywhere on the outlet is fine. I'd do it as you have demonstrated. The operation of the gate valve in that location would do exactly the same thing as twisting to pipe (letting more or less water out).

Just leave your pipe in the fully open position and let the valve do the restricting. No need to even glue the valve in place so you can try this now.